E3 ubiquitin-protein ligase which promotes ubiquitination of YBX1, leading to its degradation by the proteasome. May play a role as a scaffold protein to promote the assembly of the p53/TP53-MDM2 complex, resulting in increase of MDM2-mediated ubiquitination and degradation of p53/TP53; may function as negative regulator of p53/TP53, leading to both apoptosis and cell growth.

Tissue specificity

Highly expressed in the placenta and testis. Expressed at lower levels in the brain, heart, kidney, liver and lung. Overexpressed in esophageal cancer.